Water injection method for assisting in recovery of heavy oil

摘要

A steam-assisted gravity drainage or cyclic steam injection method for recovering oil from a development region of an underground reservoir, further employing water injection along one or more peripheral side edges of the development region via a horizontal well or wells to thereby bound the development region on at least one side edge thereof, and preferably along two or more side edges, with water to thereby reduce steam loss from the development region and thus reduce steam-to-recovered oil ratio (SOR). The water may be combined with diluents. The water which is injected into the horizontal well or wells may comprise produced water recovered from said reservoir.

主权项

1. An improved thermal oil recovery method for recovering oil from a development region of a hydrocarbon-containing subterranean reservoir, comprising the steps of:
(i) drilling a first heated fluid injection well, having a horizontal portion extending into said development region and adapted for injecting a heated fluid into said development region; (ii) drilling a first production well within said development region, having a horizontal portion situated parallel with but positioned below said horizontal portion of said first heated fluid injection well, said production well adapted for collecting heated oil from said development region; (iii) drilling at least one liquid injection well along at least one side edge of said development region; (iv) injecting a heated fluid such as steam into said first heated fluid injection well and into the development region via said horizontal portion of said heated fluid injection well; (v) injecting a liquid such as water into said liquid injection well along said one side edge of said development region to create a pressurized zone at said one side edge to reduce flow of the heated fluid and/or heated oil past said pressurized zone; and (vi) collecting and producing to surface the heated oil within said reservoir that has flowed into said production well.